Fermentative process for the production of sorbose



July 16, 194m J. WEIJLARD El AL FERMENTATIVE PROCESS FOR THE PRODUCTION OF SORBOSE vFiled Nv'. 5, 1956 2 sheets-sheet 1 fmmmwmmm FERMEN'I'ATIVE PROCESS FOR THEI PRODUCT-ION OF SORBOSE Filed Nov. 5,'193@ 2 Sheets-Sheet 2 Patented July 16, 1940 UNITED STATES PATENT OFFICE FERMENTATIVE PROCESS FOR THE `PRODUCTION OF SORBOSE Application November 5, 1936, Serial No. 109,302

3 Claims.

This invention relates to a process for the production of sorbose.

The primary object of the invention is the production or manufacture of sorbose from a crystalline hexahydric alcohol known as sorbitol. According to our invention, the sorbitol in aqueous solution is subjected to bacterial oxidation with Acetobacter suboydans, killed yeast being used as nutritive media, air under pressure being then forced through the foregoing solution, to effect the conversion of the sorbitol into sorbose.

The new process for the manufacture of sorbose further includes the steps of filtering the finished solution and concentrating the same in vacuo to produce a syrup which crystallizes in a wateralcohol mixture. This results in a yield of as high as 80 to 85 percent of sorbose.

Other objects of the invention will appear in the following description of the process which may be carried out in an apparatus such as that shown in the accompanying drawings, wherein Figure 1 is a vertical sectional view of an apparatus for the production of sorbose and disclosing a cylindrical chamber divided by a porous plate into an upper liquid chamber and a lower air chamber,

Figure 2 is a detailed sectional view taken on line 2-2 of Figure 1, showing sight glasses in the cover wall of the receptacle.

Figure 3 is a cross-sectional view taken on line 3-3 of Figure 1,

Figure 4 is a detailed sectional view taken on line 4-4 of Figure 3, showing the liquid and airtight connection between the upper and lower chambers of the receptacle and the porous partition plate forming the chambers, and

Figure 5 is a detailed sectional view taken on line 5-5 of Figure 1.

The apparatus for the practice of our improved process for manufacturing sorbose according to our invention, may be of any preferred construction, an example thereof as illustrated comprising a cylindrical receptacle I0 including a metallic cylinder I I with a vitreous or glass cylindrical lining I2. The lower end of the cylinder II carries an outwardly directed angular flange I3 which mates with outwardly directed angular flange I4 carried by the upper edge of a base receptacle I5.

As shown more clearly in Figures 1 and 4, a porous plate or disk I6 is positioned between the mating flanges I3 and I4 to provide a. chamber I'I in the cylinder II that is separated from the chamber I8 in the base receptacle I5. An elastic or rubber ring I9 of U shape in cross section incloses the marginal edge of the porous disk I6 and rubber ring gaskets 20 are respectively positioned between the rubber ring I9 and the flanges I3 and I4. A split metallic band 2| surrounds the porous disk I6 to retain the rubber ring I9 in position, the ends 22 of split band 2| being secured together by the nut and bolt combination 23. C- shaped clamps 24 carrying adjusting screws 25 are clampingly engaged with the anges I3 and I4 of the metallic cylinder II and the base receptacle I5 to provide a liquid and air-tight connection between the cylinder and base receptacle as will be evident from an inspection of Figure 4.

A pipe 26 is in communication with the chamber I8 in the base receptacle I5, the pipe 26 having a valve controlled pipe 21 in communication therewith to control the flow of ltered air into the chamber I8 while said pipe 26 has also a valve controlled pipe 28 communicating therewith for the delivery of steam to the chamber I8. The valve controlled drain pipe 29 extends from the bottom wall of the base receptaclev I5.

As shown more clearly in Figures 1 and 2, the upper end of the metallic cylinder I I is outwardly ilanged as at 30 for the support of a. cover that comprises a steel disk 3| having the bottom face thereof covered by block tin 32, the cover 3| having a series of upstanding pipes or tubes 33 to facilitate introduction of the sorbitol-yeast solution and also the introduction of the inoculating suspension of Acetobacter suborydans, as Well as providing for the normal escape of air. Sight glasses 34 are also carried by the cover 3| so that the reaction process may be inspected.

A valved sampling pipe 35 projects from the cylinder II adjacent the lower end thereof and above the porous plate I6.

In practicing oui` process with the apparatus disclosed, then, the entire cylinder is sterilized with steam through pipe 28, the sterile solution is placed in chamber I1, and filtered airis delivered to chamber I8, whereupon the culture of Acetobacter suboydans is added. As an example, the sterile solution delivered to chamber I'I may have the following composition: 25 kg. or sorbitol, 2.5 kg. of yeast, and 250 liters of water. The porosity of the plate I6 is such that when air under pressure of approximately 10 to 12 cm. of mercury enters the chamber I8 in the base receptacle I5, the air will be forced through the porous plate I6 and upwardly through the 100 cm. column of liquid in the chamber I1, the air being evenly distributed throughout the liquid in the form of minute bubbles, thereby providing intimate contact in order to effect the conversion.

In approximately six days. the conversion is about 70% complete. The liquid is thm ltered. concentrated in vacuo to a mun and naliy crystallized in a waterfulcohoi mixture. A yield of 60 to 65% sorbose is thus obined.

in another example of the process, 2% of sorbitol ma;1 be used with respect to a @ven quantity oi yeast-water and the time required to eiect conversion to about '70% of theory is approximately 12 days.

From the above description of the process, it is believed that the production of sorbose from a sorbitol material will be readily apparent. The steps of the process comprise preparing a solution of sorbitol in bakers yeast-water, sterilizing. inoculating with Acetobacter suboydans, and causing ltered air to percolate upwardly under pressure through a porous plate into the liquid in an upper chamber in the receptacle, producing minute bubbles with subsequent oxidation of the sorbitol in the solution, and thereafter ltering. concentrating and producing sorbose in crystallized form.

The process described herein for aiecting the desired conversion described herein is distinguished from processes of the prior art in that a relatively high percentage of sorbotol may be employed. Thus, commercially applicable concentrations of as high as 20% sorbitol have been momes employed satisfactorily, whereas in the processes hitherto employed, only concentrations of serbitol up to about 3% have been used.

We claim as our invention:

1. The process for producing sorbose which comprises forcing air through a solution consisting of more than 3% and up to 20% of sorbitol in yeast water inoculated with Acetobacter suhoydans, filtering and concentrating the liquid in vacuo, and then crystallizing the concentrated liquid in a Water-alcohol mixture.

2. The process for producing sorbose which comprises preparing a solution consisting of 25 kg. of sorbitol and 2.5 kg. of yeast in 250 liters of water inoculated with Acetobacter suborydans, forcing air through the solution to eiect the reaction in the presence of the bacteria, ltering. concentrating, and crystallizing the syrup in a water-alcohol mixture.

3. In a process for producing sorbose from sorbitol, the step which comprises forcing air under pressure through a solution consisting of from 3 to 20% sorbitol in yeast water inoculated with Acetobacter subozyda'ns.

` JOHN WEIJLARD.

WILLIAM H. ENGEIS. CHRISTIAN V. HOLLAND. 

